The graduation design based on the design plan descriptions of the construction of national economy and policy， the policy， technology， combined with the actual engineering prescribed line， ensure reliable power supply， scheduling， meet the technical requirements for On the analysis of the original material， on the basis of 110 kv substations electrical design project of the connection mode of operation are analyzed， 110 kv substations is elected meet safe， reliable quality， and the economic operation of the requirements of 110 kv substations wiring way as the normal operation and auto-switch For the main electrical wiring， short-circuit current calculation， to reasonably select the electrical Finally， according to the first part of the wiring and requirements of the relay protection， substation configuration， in order to ensure the safe and economic operation， prevent accidents or expansion， the safe and economic Integrated substation automation are the second equipment (including substation measuring instruments， signal system， relay protection and remote device and automatic device etc) through the combination of function and the optimization design， the use of advanced computer technology， modern electronic technology， the communication technology and the signal processing technology， the main equipment of the transformer substation， power distribution lines and automatic monitoring and measurement， automatic control and microcomputer protection， and scheduling communication etc comprehensive automation Keywords:Substation， The main electrical wiring， Transformer， Circuit breaker， Isolating switch， Bus， Short-circuit current， Relay protection， Control and
Among modern power system，power equipment has a large Besides，as the operation of each component is complex，it is easy to cause varous forms of electrical Therefor，rely protections measures must be taken to make the system operate more This paper researches and desighs relay protectiong of 110KV power 。。。。。。
